Motor-control apparatus.



- D. WALD, 0. G. BRITSCH & M. TAIGMAN.

MOTOR CONTROL APPARATUS.

APPLICATION FILED APR. 23, 1910.

. Patented Feb. 14, 1911.

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MOTOR CONTROL APPARATUS.

APPLICATION rum) 141.23, 1910.

Patented Feb. 14,1911.

WIN/E8858 My M a m M n U mam D. WALD, O. O. BRITSOH 6: M. TAIGMAN.

MOTOR CONTROL APPARATUS.

APPLICATION FILED APR. 28, 1910. I

Patented Feb. 14, 1911.

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ATTORNEYS DAVID WALD, OTTO C. BRITSCH,

AND MAX TAIGMAN, OF NEW YORK, N. Y.

' MOTOR-CONTROIE APPARATUS.-

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Specification of Letters Patent.

Patented Feb. 14, 1911.

v Application filed April 23, 1910. Serial No. 557,151.

To all wiiojn My concern:

Be it known that we, DAVID \VALoand O'r'ro C. BnrrscH, citizens of the United States, and both residents of the city of New York, borough of Manhattan, in the county and State of New Yorln-and MAX 'lAIGMAN, a citizen of the United States, and a resident of the city of New York,

borough of Brooklyn, in the county of Kings and State of New York, have invented a new and Improved Motor-Control Apparatus, of which the following is a full,

clear, and exactdescription.

This invention relates to motor control apparatus, and has reference more particularly to apparatus of this class which serves for exactly controlling the operation of electric motors,-to' startand stop the same, or to vary the speed, and which has resistances, means for including the resistances singly or in groups in the motor circuit, and also means for automatically stopping the'motor under certain conditions.

An object of the invention is to provide simple and efiicient apparatus for controlling electric motors, which can be used for various v purposes, though particularlyuseful in connection with motor-driven sewing machines or the like, which is rapid and positive in operation, which can be operated by means of a pedal, and-which, when the pedal or corresponding part is released, automatically stops the motor.

A; further object of the invention is to provide motor control apparatus which can be easily and expeditiously taken apart and puttogether, which can be mounted in position without necessitating changes in the machine to which it is applied, and which has associated therewith a brake for bringing the motor rapidly to a stop.

The invention consists in the construction and combination of parts to be more fully described hereinafter and particularly setforth'in the claims.

Reference is to be had to the accompanying drawings forming a part of this specification, in which similar characters of ref erence indicate corresponding parts in all the views, and in which 7 Figure 1 is a side elevation of a motordriven sewing machine having an embodiment of our'invention applied thereto; F ig. 2 is a diagrammatic View showing the motor, the resistances, and the circuit-making and breaking means; Fig. 3 is a side elevation of the apparatus, having part of the casing removed; Fig. 4: is a longitudinal section on the line 4% of'Fig. 3; Fig. 5 is a transverse section on the line 55 of Fig. 3; Fig. 6 is a side elevation showing the re sistance coil and the contacts removed from the casing; Fig. 7 is a fragmentary, transverse section showing details of modified form; and Fi 8 is a cross section on the line 8Z- of Fig. 7.

Before proceeding to a more detailed ex: planation of our invention, it should be clearly understood that while We have shown the apparatus used for, controlling the motor of a sewing-machine it can be advantageously employed in connection with motors used for different purposes. In the present instance, the treadle of the sewingmachine is used to operate the control apparatus, so that the hands of the machine operator'are leftfree for manipulating the work. A special pedal maybe provided for the-purpose, or other means can be used for operating the control apparatus. This and others of the constructive details can be varied in accordance with special conditions and individual preference, without departing from the underlying spirit of theinvention.

Referring more particularly to the draw ings, we have shown for example, a sewingmachine having supports or legs 10, a table 11 carried thereby, and a sewing mechanism 12 mounted on the table and having a pulley 13.v Positioned underneath thetable 11 is an electric motor 14. of any suitable form having associated therewith a driving pulley 15 operatively connected by means of a suitable belt 16, with the pulley 13. Pivotally mounted between the supports, near the lower ends thereof, is a treadle 17 which is used, as will appear hereinafter, for operating the motor control apparatus. This includes a; casing 18 of metal orother suitable material secured to an insulating plate 19 by] means of lugs 20 screwed or otherwise fas toned in position. The insulating plate 19 is mounted in any convenient manner at the under side of the table, and may consist of a slab of slate. or any other materialadapted tor the purpose. 4

The bottom 21 of the casing'is removable,

having at the: rear edge a lug 22 adapted to be secured to the back 23 of the casing, by a suitable screw 24. Carried by the bottom, upon suitable insulating disks 25, are resistance coils 26, three or more in number and of the usual form. An insulating slab 27 is fastened by means of a screw 28, at a projection 29 of the bottom of the casing and extend'supwardly to the top 30 of the casing, engaging a lug 31 of the top, which serves to hold the slab in lace. A channel 32 receives the slab and is mounted upon the bottom. A screw 33 mounted in a suitable, threaded opening of the end wall 34 of the casing can be forced against the channel 32 to jam the insulating slab against the lug 31 to hold the parts in place. The insulating slab has contacts 35, 36 and 37 of metal or other suitable material. These contacts are preferably disks, and have associated therewith electrical conductors 38, 39 and 40. The conductor 38 is connected with one of the terminals of a resistance coil 26. The conductor 39 is connected with the opposite terminal of the same coil and with a corresponding terminal of an adjacent coil. The conductor 40 is connected with the opposite terminal of the last-mentioned, adjacent coil, and with the corresponding terminal of the third coil. The insulating slab has a further contact-41 of elongated form. and-connected by means of a conductor 42 with the remaining terminal of the last-mentioned coil 26.

A binding post 43 is arranged upon an insulating plate 44 which, togetherwith an insulating member 45 at the inside of the bottom serves to isolate the bindin 0st electrically from the casing. The inn ing post is connected by means of a conductor 46 with the conductor 38 and the terminal of the coil 26 to which this last-mentioned conductor 38 runs.- A second binding post 47 is mounted upon the insulating plate 44 and is electrically connected with a metallic or other terminal plate 48 positioned within the casing on an insulating plate 49, mounted upon the bottom, for a purpose to appear hereinafter. 1

The end wall 50 of the casing opposite the end wall 34 has an opening 51, and adjacent thereto an extension 52 having a bore 53 in which is movably mounted a spindle 54. A contact'arm 55 has a hub or barrel 56 by means of which it is mounted upon the spindle 53 and extends through the opening 51, into the casing. It is formed in two parts separated by aninsulating plate 57 and has lugs 58 held together by screws 59, or in any other suitable manner. The contact arm at the outside of the casing has an extension 60 connected by means of an adjustable link 61 with the treadle 17, so that the contact arm can be operated by means of the treadle. f

' At the inner end, the contact arm has a.

collar 62 in whichis slidably positioned a transverse contact stub 63, normally pressed toward the insulating slab 27 bya spring 64 mounted upon the arm and enga ing at the end of the stub. The arm, at the ower edge,

has a downwardly ofiset extension 65 to which is pivotally secured by means of a screw 66, a movable circuit-making member 67 which has at the free end a shoe 68 normally resting upon the terminal plate 48 and effecting electrical connection therewith. Intermediate its ends the circuit-making member has a recessed enlargement 69 in which is positioned a projecting stud 79 of insulating material, for a purpose to appear hereinafter.

The casin has a face plate 71 having at the upper e ge undercut flanges 72 adapted to engage over lugs 73 of the. top of the casing. At the lower edge, the face plate has an inwardly disposed flange 74 carrying holding screws 75 adapted to engage at the inside of inclined lugs 76 on the bottom of the casing, so that the face plate can be removably secured in position to inclose the coils and the other parts of the apparatus.

An arm 77 having an enlargement 78 is secured to the wall 50 of the casing, b means of a bolt or screw 79 passing throug an opening of the enlargement. The arm at the end has an extenslon 80 at which is pivotally mounted, by means of a screw 81 or the like, alever 82. The latter has an end 83 loosely received by an opening 84 near the outer end of the contact arm. The lever 82 at its free end, carries a brake shoe 85 adapted to engage the pulley 15 of the motor to bring the same to a stop when the contact arm is in its depressed position. A spring 86 is secured at the outer end of the contact arm to the pedal 11 of the machine,

and tends to hold the contact in a normal position.

In the operation of the device, when the user presses on the treadle 17, the arm is swung upward and moves along the contact 41, until. the circuit-making member 67 reaches a position. such that the insulatin stud is disengaged from the termina plate 48, and the shoe 68 is brought into enga ement with the plate, to close the aircuit. Current will then flow through all three of the resistance coils to the motor. By depressing the treadle further, the arm is moved to the next contact, that is to the contact 37, thereby cutting out one of the coils. To bring the motor to a higher speed the arm is movedupward still farther, until it engagesthe contact 36 and then 35. The remaining resistance coils being thereby successively cut out of the circuit. When it is desired to stop the motor, the pressure upon the-treadle is released, and the spring 86 thereupon returns the parts to their original positions. As soon as the insulating stud 70 engages the terminal plate, the shoe 68 is disengaged from thelatter and the circuit is broken.

In Figs. 7 and 8 we have illustrated a modified form of our invention in which the spindle 87, corresponding to the spindle 53, is extended through the casing and at its outer end has a sleeve 88 secured thereon by means of a set screw 89. The sleeve 88 carries rigidly, a transverse sleeve 90 in which is positioned a rod 91 held in place by a set screw 92. The rod 91 carries a brake shoe 93 adapted to engage the pulley 15, so that when the spindle is pivotally operated by the movement of the contact arm the brake shoe is brought into or out of engagement with the pulley.

\Vhile we have shown and described, for example, the form of our invention which is controllable by atreadle adapted. to be actuated by the foot of the'operator of the machine, any other device controllable at will by the operator, ,for maintaining the arm operative against the tension of the spring can be used with equal advantage under certain circumstances. We do not wish to limit ourselves to this feature, as well as to others of the constructive details, and shall, in the claims hereinafter, employ the term means for manually con-- trolling the contact arm in a generic sense.

Having thus described our invention, we claim as new, and desire to secure by Letters Patent z- V 1. In apparatus of the class described, a plurality of resistances, a movable contact arm, a plurality of contacts, each electrically connected with one of said resistances, said contact arm being adapted to engage each of said contacts to form an electrical connection therewith, acircnit-mahing membei-nss'ociated With saidarm, said member being operative when said arm is in engagement with each of said contacts, said member being inoperative, furthermore, when said arm in in engagement with one of said contacts.

2. In apparatus of the class described, a movable contact arm having mevably associated therewith a circuit-making member, a terminal adapted to be engaged by said member to form an electrical connection therewith, a plurality of contacts each adapted to be engaged by said arm when said member is in engagement with said'terminal, and means carried by said member whereby said member is out of electrical contact with said terminal when said arm is in engagement with one of said contacts.

3. In apparatus of the class described, a

plurality of. resistance coils, a plurality of contacts, conductors connecting said contacts and said coils, a movable contact arm adapted to engage each of said contacts, a

gage said terminal in one terminal to form an electrical connection therewith when said arm is in engagement with each of said contacts, said member hav ing an insulating part adapted to engage said terminal to break the circuit when said member is in a predetermined position.

4. The combination, with a motor, of control apparatus comprising a plurality of re sistances, contacts electrically connected with said resistances, a terminal, conductors for connecting said terminal and said motor with a. source of electrical supply, a conductor connecting said motor and said resistances, said contact-s being insulated from one another, a movable contact arm adapted to engage each of said contacts to form an electrical connection therewith, and a circuit-mah'ing member movably associated with said arm and adapted to engage said terminal to form an electrical connection therewith when said arm is in engagement zliillll each of said contacts, said member having an insulated part adapted to engage said terminal, whereby said member isout of electrical connection therewith, one of said contacts being of elongated form, whereby said member can both be in electrical connection or out of electrical connection with said terminal. while in engagement with said last-mentioned contact. j

The combination, with a motor, of con-1 trol apparatus comprising a plurality of re"- sistance coils, contacts insulated from one another, a movable contact arm adapted to engage said contacts, a terminal, conductors connecting said terminal and said motor with a sonrceof electrical supply, a conductor connecting said motor with one of said coils and one of said contacts, further conductors connecting the others of said contacts with saidcoils, and a movable circuitmaking member associated with said contact arm and adapted to engage said terminal and having an insulating part adapted to can position of said member. I

6. The combination, with a motor, of control'apparatus comprising a plurality of re-' sistance coils, contacts insulated from one another, a movable contact arm adapted to engage said contacts, a terminal, conductors connecting said terminal and said motor with a source of electrical supply, a conductor connecting said motor with one of said coils and one of said contacts, further conductors connecting the others of said contacts with said coils, a movable circuit-making member associated with said contact arm and adapted to engage said terminal, a spring tending to maintain said contact arm inoperative, and means for holding said arm engaged by said necting said contacts and said resistances,

' minal to break the motor circuit,

whereby said resistances are successively included in or excluded from the motor circnit, when said arm is brought into successive engagement with said contacts, said circuit-making member having an insulated part, whereby when said arm is in a predetermined position said part engages said terminal to break the iiiotorcircuit.

8. Apparatus of the class described, comprising a plurality of resistances, a terminal, conductors for connecting said terminal and said resistances with a motor, a movable con tact, arm, a circuit making member associated with said arm and adapted to engag: said .terminal, contacts, each adapted to engaged by'said arm, and conductors connecting said contacts and said resistances, whereby saidresistances are successively included in or excluded from the motor circuit, when-said arm 18 brought into successive engagement with said contacts, said circuit-making member having an insulated part whereby when said arm is in a redetermined position said part engages said terone of said contacts being elongated, whereby said member can be in electrical engagement with said terminal or out of electrical engagement therewith when said arm isin engagement with said lastmentioned contact.

V spring tendinglto hold said arm in a prede 9. Apparatus oi the class described, comprising a casing, resistance coils mounted therein, a terminal insulated from said casing, an insulating slab, contacts mounted upon said slab, a pivoted contact arm adapted to engage said contacts, a circuit-making member pivotally carried by said arm and. adapted to engage said terminal, and means for operatmg said arm.- v

10. Apparatus of the class described, comprising a casing, resistance coils mounted therein, a terminal insulated from said casing, an insulating slab, contacts mounted upon said slab, a ivoted contact arm adapted to engage sai contacts, a circuit-making member pivotally carried by said arm and adapted to engage 'saidtermin al,"manually controllable means for operating said arm, a

termined position, said circuit-making member having an insulated part adapted to enarm, and conductors con position,

-with a lug, said slab being arrange -screw mounted at said end wall and adapted opening therein, resistances within gage saidterminal to break the circuit in a predetermined sition of said arm, and means for electrically connecting said terminal and said contacts with a motor circuit.

11. Apparatus of the class described, coniprising a casing having a removable bottom, resistances carried by said bottom, contacts carried by said bottom and connected with said resistances, a movable contact arm piv-' oted with respect to said casing and adapted to engage said contacts, and a removable face plate adapted to beseciired to said casing and said bottom thereof.

12. Apparatus of the class described, comprising a casing havingoa back, a top and end walls, a removable t-tom having a lug, said back having a screw adapted to be secured at said lug -to hold said bottom in a face plate having undercut flanges atthe upper edge, said to having lugs adapted to be received-b sai fla es, said bottom having inclined h1g5, said ace plate, at the lower edge having a laterally disposed flange provided with screws adapted to engage said inclined lugs to secure said face plate in position, resistances within said casing, contacts associated with said resistances, and a contact'arm pivoted at an end wall of said casing and adapted to engage said contacts.

13. Apparatus of the-class described, comprising a casing having a back, and an end wall, a bottom removably secured to said back, an insulating slab mounted upon said bottom, said casing having a top (provided to abut against said lug, means carried by said end wall for clamping said slab against said lug, resistances carried by said bottom, contacts carried by said slab and electrically connected with said resistances, and a contact armadapted to engage said contacts.

14. In apparatus of the class described, a casing having a back, an end wall and a top, said top 'havin an inwardly extending lug, a removable ottom secured to said back, an insulating slab mounted upon said bottom and adapted to engage said In a channel receiving an edge of said sla a to engagesaid channel to force said slab against said lug, resistance coils-mounted upon said bottom, a pivoted contact arm projecting into said casin and contacts mounted upon said slab an "adapted to be. engaged by said arm, said contacts being electrically connected with said coils.

15. In apparatus of the class described, a casing having said casin contacts within said casing and electrically connected with said resistances, said end wall adjacent to said 0 ning havi an enlargement, resenting a re, a spind e in: f said bore, an a contact arm an end wall provided with an d having a hub 13o mounted upon said spindle, and extending t ln'ough said opening into said casing, and adapted to engage said contacts.

16. In apparatus of the class described, a casing having an end wall provided with an opening therein, resistances within said casing, contacts within said casing and electricallyconnected with said resistances, said end wall adjacent to said opening having an enlargement, presenting a bore, a spindle in said bore, a contact arm having a hub mounted upon said through said opening into said casing and adapted to engage said contacts, said arin,

15 at the outside of said casing ha\-'ing an exspindle and extending tension, a lever pivotally mounted upon saidcasing and operatively engaged by said extension of said arm, and a brake-shoe carried by said lever and adapted to brake a motor controlled by the apparatus.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

DAVID WVALD. OTTO C. BRITSGH. MAX TAIGMAN. 

